Reflective Nested Simulations Supporting Optimizations within Sequential Railway Traffic Simulators

This article describes and discusses railway-traffic simulators that use reflective nested simulations. Such simulations support optimizations (decision-making) with a focus on the selection of the most suitable solution where selected types of traffic problems are present. This approach allows suspension of the ongoing main simulation at a given moment and, by using supportive nested simulations (working with an appropriate lookahead), assessment of the different acceptable solution variants for the problem encountered—that is, a what-if analysis is carried out. The variant that provides the best predicted operational results (based on a specific criterion) is then selected for continuing the suspended main simulation. The proposed procedures are associated, in particular, with the use of sequential simulators specifically developed for railway traffic simulations. Special attention is paid to parallel computations of replications both of the main simulation and of supportive nested simulations. The concept proposed, applicable to railway traffic modelling, has the following advantages. First, the solution variants for the existing traffic situation are analyzed with respect to the feasibility of direct monitoring and evaluation of the natural traffic indicators or the appropriate (multi-criterial) function. The indicator values compare the results obtained from the variants being tested. Second, the supporting nested simulations, which potentially use additional hierarchic nesting, can also include future occurrences of random effects (such as train delay), thereby enabling us to realistically assess future traffic in stochastic conditions. The guidelines presented (for exploiting nested simulations within application projects with time constraints) are illustrated on a simulation case study focusing on traffic assessment related to the track infrastructure of a passenger railway station. Nested simulations support decisions linked with dynamic assignments of platform tracks to delayed trains. The use of reflective nested simulations is appropriate particularly in situations in which a reasonable number of admissible variants are to be analyzed within decision-making problem solution. This method is applicable especially to the support of medium-term (tactical) and long-term (strategic) planning. Because of rather high computational and time demands, nested simulations are not recommended for solving short-term (operative) planning/control problems.

GC- and UHPLC-MS Profiles as a Tool to Valorize the Red Alga Asparagopsis armata

Asparagopsis armata Harvey is a red alga native from the southern hemisphere and then introduced in the Mediterranean Sea and the Atlantic Ocean, including the Azores Archipelago, where it is considered an invasive alga. Some studies show that the extracts exhibit antimicrobial and antifouling activities, and it is incorporated in some commercialized cosmetic products. (e.g., Ysaline®). However, knowledge of this species chemical composition is scarce. The GC-MS and UHPLC-MS profiles of both the nonpolar and polar extracts were established to contribute to this problem solution. According to the results, A. armata is rich in a great structural variety of halogenated lipophilic and aromatic compounds, some of them identified here for the first time. In the lipophilic extract, 25 compounds are identified, being the halogenated compounds and fatty acids, the two major compound families, corresponding to 54.8% and 35.7% of identified compounds (224 and 147 mg/100 g of dry algae, respectively). The 1,4-dibromobuten-1-ol and the palmitic acid are the two most abundant identified compounds (155 and 83.4 mg/100 g of dry algae, respectively). The polar extract demonstrated the richness of this species in brominated phenolics, from which the cinnamic acid derivatives are predominant. The results obtained herein open new perspectives for valuing the A. armata as a source of halogenated compounds and fatty acids, consequently improving its biotechnological and economic potential. Promoting this seaweed and the consequent increase in its demand will contribute to biodiversity conservation and ecosystem sustainability.

The challenges of empowering waqf land in Indonesia: an analytical network process analysis

Purpose This paper aims to identify the factors that hinder the successful empowerment of waqf land in Indonesia empirically by applying the analytic networking process (ANP). Design/methodology/approach In this study, after the waqf land problem criteria were introduced, an ANP model was developed and applied to identify the main problem, solution and strategy as a framework to guide stakeholders to produce policy recommendations appropriately and optimally. Findings The results showed that the main priority of the problem is the nadzir aspect. Furthermore, each criterion’s problems are a low public trust, unprofessional nadzir (waqf manager), a huge number of idle waqf lands, the absence of waqf certificates and non-economic waqf lands utilisation. Meanwhile, the main priorities for each aspect of the solution are socialisation and education to the community, nadzir certification, utilisation of information technology for the administration of waqf land governance, waqf land certification and innovation of waqf land development projects. Then, the long-term strategic priority is optimising the community’s role in the empowerment of waqf land. Research limitations/implications The development of the ANP model would give the institutions a modest, flexible and convenient approach to evaluate the barriers present in waqf land. However, ANP requires greater effort because it is a highly complex methodology that compels a study to use more numerical calculations in assessing composite priorities. Originality/value Not many studies on waqf land issues in Indonesia have been discussed empirically. Most of these studies are in the form of descriptive studies. This study introduces the ANP approach to illustrate the main problems of waqf land empowerment in Indonesia. ANP is a new approach to the decision-making process through a process that produces a general framework for treating decisions without making assumptions regarding independence between elements.

Information-statistical approach to inverse optical problem solution for 3D disperse systems with nano- and micro particles

Multiparameter analysis of simultaneous optical data for 3D disperse systems (consisted from nano- and/or microparticles of different nature) by information-statistical methods can help to estimate the share of different types of particles in mixtures. At the solution of inverse optical problem for unknown poly-component 3D DS, the comparison of measured parameters with the known ones from the set of mono-component 3D DS can help to identify the component content of the system under study. The approach was tested on the biomineral water mixtures of kaolin clay and bacterium coli bacillus with the help of the program based on the information-statistical theory. To solve the impurity optical recognition tasks, the Base of optical data for 3D DS is needed.

Issues, Challenges and Opportunities of Agriculture in West Kameng District of Arunachal Pradesh

A survey was made during ‘Kisan Jawan Vigyan Mela’ at Defence Research LaboratoryResearch and Development Centre (DRL R&D Centre), Salari, West Kameng district ofArunachal Pradesh with an aim of getting insight of issues, challenges and opportunitiesof agriculture sector. The relevant data was collected during Mela from 67 farmers of 11villages of the district using semi-structured interview (SSI) and a rank-based quotient (RBQ)was worked out to rank the farmers issues and challenges. Based on ranking of problemsby the group of farmers, outbreak of insect-pest and diseases, paucity of quality seedmaterial of field and vegetable crops and lack of technical knowhow were found to be themajor issues and challenges of the region. The problem solution trees for three of the majorproblems were constructed and the opportunities in hill farming were suggested to thefarmers as per the impact analysis and RBQ.

Combined optimisation and MCDA based solution of the tram depot location problem

This paper deals with an issue of technical facilities location in a public transport system. The decision problem is formulated as a selection of the most advantageous alternative, i.e. the location of a new tram depot among the already existing facilities of this type. The selection is preceded by the evaluation of the alternatives. The assessment is not a trivial task, because there are many groups of interest with usually contradictory points of view. Therefore, the evaluation of the new tram depot locations should represent different aspects, e.g., economical, technical, environmental, and organizational. To handle such a complex decision problem the authors propose a methodology, which is a composition of the optimisation and multiple criteria evaluation techniques. The developed methodology is experimentally applied to the selection of one out of five tram depot locations in the public transport system of the city of Poznan, Poland. All the computational experiments are performed by means of optimization and multiple criteria decision aiding (MCDA) methods and tools, i.e. a linear optimization engine Solver Premium Platform and AHP method with its application AHORNsimple. The calculations are the basis for recommending the location of a new depot in the central part of the transport system network, which is a reasonable solution taking into account, e.g. the proximity of the main railway line, the possibility of triple distribution of the transport means from depot. The proposed methodology of the decision problem solution gives also an opportunity to create the hierarchy of considered tram depot locations as well as to compare the position in the ranking of the best solution with the existing one. Since the proposed methodology assumes the selection of the most suitable MCDA method to the problem under consideration and the decision maker’s preferen¬ces, it guarantees that the result of analysis becomes reliable and the decision aiding process is credible.